Scale.



No. 649,943. Patented May 22, I900. W. F. C. MORSELL.

SCALE.

(Application filed June 12, 1899.) (No Model.) 2 Sheets-8heet FZGJ- va). 5 6 $2M, WITNESSES: INVENTOR:

THE noams PETERS o0. PHDYQ-LITHCL, WASHINGTON, D. c

No. 649,943. Patented May 22, I900.

W. F. C. MURSELL.

SCALE;

(Application filed June 12, 1899.)

(No Model.) 2 Sheets-*Sheet 2.

w. 1. 6mm;

WITNESSES: 7 INVENTOR:

Urvrran STATES PATENT FFICE.

IVILLIAM F. C. MORSELL, OF PHILADELPHIA, PENNSYLVANIA.

SCALE.

SPECIFICATION forming part of Letters Patent No. 649,943, dated May 22,1900.

Application filed June 12, 1899. Serial No. 720,274. (No model.)

f0 all whom, it may concern.-

Be it known that LWILLIAM F. O. MORSELL, a citizen of the United States,residing in the city and county of Philadelphia, in the State ofPennsylvania, have invented certain new and useful Improvements inScales, of which the following is a description.

It is the object of, my invention to provide a balancing connection orcontact between the balance bar and the body of a scale, of suchcharacter that said bar shall be very sensitive and responsive to themost minute degrees of weight,of such form and arrangement that thecontacting parts are not only subject to the minimum of wear in actionbut are practically unaffected in delicacy and accuracy by any suchslight wear of the parts as does occur,-and provided with devices bywhich misadjustment of the contacting parts may be instantaneously andeasily corrected or such contacting parts be physically maintained inoperative relation for ordinary weighing in which very great miuutenessand accuracy are not required.

This object I accomplish in the apparatus illustr'ated'by providing asupporting arm equipped withrounded upwardly extending projections, anda balance bar having trunnions the lower faces of which are rounded andrest and bear upon the rounded projections of the arm, with the resultthat the balance bar with its usual attachments, on the one hand, andthe supporting arm, on the other hand, are in contact with each otherthrough such oppositely disposed rounded faces.

The balance bar, therefore, in the apparatus illustrated, rests androlls on the rounded faces of its trunnions upon a rounded surface fixedwith respect to and constituting in effect a part of the fixed arm ofthe scale, and the contact between these two rounded surfacesconstitutes the only contact, when the parts are in a given position,between the balance bar and the body of the scale, with the result thatthe balance bar is exceedingly sensitive and responsive to weights ofinfinitesimal character.

My invention further com prehends the provision of a centering andretaining cage, as I term it, by which the balance bar may be restoredto proper position should its rounded faces by any means slip laterallyfrom the rounded supporting faces of the arm, and by which,furthermore,when articles as to which no great accuracy is desired" areto be weighed, the rounded surfaces of the bar may be held in positionupon the rounded surfaces of the arm during such weighing.

' In the accompanying drawings I show, and herein I describe, a goodform of a convenient embodiment of my invention, the particularsubject-matter claimed as novel being here inafter definitely specified.

It is to be understood that the embodiment of my invention representedin the drawings and herein described is typical merely and susceptibleof innu merable changes and variationsin construction and arrangementWithout departure from the spirit of my invention.

In the accompanying drawings, Figure 1 is a vertical, sectional,elevation, through the supporting standard, the supporting arm, and thebalance bar, of a scale embodying my invention.

Figure 2 is a view in perspective of the supporting arm.

Figure 3 is a top plan view of the centering and retaining cage. I

Figure 4 is a fragmentary sectional plan on the line 4-4 of Figure 1.

Figures 5, 6, and 7, are vertical, sectional, elevational, details onthe dotted line 02-00 of Figure 1, illustrating the respective positionsof the cage with respect to the supporting arm and balance bar. I

Figure 8 is a View in perspective illustrat ing the supporting arm, thecage, the central portion of the balance bar, and associated parts.

Similar letters of reference indicate corresponding parts.

In the accompanying drawings the body of the scale consists of a tubularstandard A vertically erected from a suitable base A, which base, in theform of my invention illustrated, embodies a horizontal recess A whichintersects the tubular bore of the standard A.

B is the supporting arm, the same consisting, in the form illustrated,of a horizontallyextending plate, the inner end or shank B of which isrigidly fixed to and conveniently disposed within the interior of thestandard A, and the body of which is divided, by a central recess 13provided for the reception of the balance bar, into the two bearingblocks B B The upper faces of these blocks are to be provided withrounded projections as stated, and I prefer to form said roundedprojections by mounting small steel spheres Z) in said upper faces.

I prefer to mount said spheres by disposing them within transverselyextending grooves I) cut in the upper surface of the bearing plates B B,which are of such shallow depth that portions of the spheres projectabove the upper faces of the plates.

The spheres are preferably of diameter corresponding to the thickness ofthe plate in was they are mounted.

The spheres are rigidly secured in position in theirgrooves in thesupporting arm in such manner as to become fixed permanent portions ofsaid arm, as for instance, by swaging in the metal at the ends of thegrooves Z), and

i the upper portions of said spheres constitute hemisphericalprojections.

C is the balance bar, of any preferred form, provided with the trunnionsD. Said trunnions D are conveniently formed by mounting a cylindricalstud in a suitable recess in said bar, as shown in Figure 1, and, saidbar, being cylindrical, itself presents or constitutes the rounded faceswhich are as hereinbefore stated to be placed in rolling contact withthe rounded projections of the supportmg arm.

When the balance bar is mounted and balanced upon the rounded surfacesof the supporting arm, it is capable of oscillation thereon, itstrunnions rolling in its movement backward and forward across therounded tops of said surfaces, and only becoming displaced or slidinglaterally from such surfaces when the bar makes a violent dip, which mayusually be avoided by careful operation of the apparatus.

E constitutes what I term a cage, the same consisting in the apparatusillustrated, of a pair of plates conveniently of the same generalprofile as the supporting arm, maintained in parallelism, and disposedone upon each side of said arm.

The supporting arm and cage are to be so arranged that one of saiddevices has vertical movement or adjustment with respect to the other,and I prefer that the cage shall be the movable member, and haveaccordingly illustrated such construction in the drawings.

, The cage is shown as a projecting structure integral with the followerF, which is disposed within and free for vertical movement with respectto the tubular standard A, the projecting members of said cage extendingthrough suitable vertical slots in the front of the standard A.

When the parts of the cage are elevated to the limit of their movement,they occupy,

with relation to the supporting arm and the balance bar trunnion, theposition shown in Figure 5, in which position, as is evident, the partsof the cage correctly center the trunnions of the balance bar upon thespheres of the supporting arm.

The position shown in Figure 5 may for the purpose of description beassumed to be the normal position of the parts, being the position inwhich the balance bar is most firmly held against accidentaldisplacement.

WVhen then it is desired to weigh on the scale pans assumed to beattached to the balance bar-,a substance the weight of which is to bedetermined with very great accuracy, the cage is lowered to the positionshown in Figure 6, in which the upper edges of the cage are below theupper surfaces of the spheres mounted on the supporting arm, leaving thetrunnions of the balance bar in balance upon the projecting portions ofthe spheres, there then being, as is obvious, no other support for thebalance bar or its trunnions.

After the weighing operation the cage may be elevated to the positionshown in Figure 5.

If, in the course of the operation of weighing, when the parts are inthe position. shown in Figure 6, the trunnions D should by anyabruptness in the movement of the balance bar, or otherwise, slip downlaterally from the spheres, and rest upon the upper edges of the cage,they may be restored to position upon the spheres by simply elevatingthe cage to the position shown in Figure 5, and then lowering it againto the position shown in Figure 6,-an operation performed in a moment.

The cage, therefore, serves as a restoring or centering device for thetrunnions of the balance bar in delicate operations of weighing.

When it is desired to weigh articles as to which no great delicacy isrequired, the cage may be set in the position shown in Figure '7, inwhich while the balance bar trunnions rest and bear upon the spheres ofthe supporting arm, the upper ends of the cage members afford suchslight lateral support as will secure said trunnions from slippinglaterally from the spheres.

Any convenient means may be resorted to for effecting the movement ofthe cage with respect to the scale arm. In the drawings I show as adevice for effecting said movement a key G formed as a tube projectingthrough the recess A of the base A and provided as to its respectiveprotruding extremities with a nut g, and a rigidly affixed sleeve 9which is equipped with a milled operating head 9 That portion' of thetube G which extends beneath the follower F is cutaway as shown, leaving'the respective extremital portions connected merely by a segment 9 H isan operating pin mounted within the interior of the tube G and adaptedfor independent rotative movement therein. Its respective extremitiesare provided with collars or projections 7L 7L which present against therespective extremities of the tube G so [surface of the arm whenaccidentally dis that the tube and pin are incapable of independentlongitudinal movement.

One end of said pin is provided with a milled operating head 7t. lhatportion of the pin which extends beneath the follower F is cut away toform the flat web 71 as shown in Figure 4.

As will be understood, when the tube G is rotated to bring its segmentinto the position shown in Figure 4, the follower F will be elevated andthe cage will be raised to the upper extreme position shown in Figure 5.

When said tube is rotated, carrying with it the pin, until the partsoccupy a position the reverse of that shown in Figure 4f, the lower endof the follower F will rest against the fiat.

face of the part 72 of the pin and the cage will then occupy the lowerextreme position shown in Figure 6.

If then, while the segment of the tube G is inits lowermost position,the pin H be slightly rotated independently of said tube, it will assumethe position shown in dotted lines in Figure 4, the follower will restupon the upturned edge of the part it of the pin, and the cage willoccupy the intermediate position shown in Figure 7.

Having thus described my invention, I claim- 1. In a scale, incombination, a scale supporting arm, having a relatively fixed convexsurface or projection, a balance bar formed with a convex surface orprojection through which said bar rests in rolling contact upon theconvex surface first named, the axis of the convex surface of thesupporting arm being in parallelism with the axis of oscillation of thebalance bar, substantially as set forth.

2. In a scale, in combination, a scale supporting arm, having a pair ofrounded or convex supporting faces fixed with relation to the balancebar, a balance bar formed with a pair of convex or rounded faces throughwhich said bar rests in rolling contact upon the rounded faces of thesupporting arm, the axis of the rounded surface of the balance bar beingin parallelism with the axis of the rounded surface of the supportingarm, substantially as set forth.

3. In a scale, in combination, a supporting arm having a pair ofhemispherical projections fixed with relation to the balance bar, abalance bar having a pair of cylindrical trunnions through which saidbar rests in rolling contact upon said hemispherical projections,substantially as set forth.

4. In a scale, in combination, a scale supporting arm, having a roundedsurface or projection fixed with relation to the balance bar, a balancebar having a convex or rounded surface through which said bar rests inrolling contact upon the rounded surface of the supporting arm, and amovable device for restoring the convex face of the bar to its positionof rolling contact upon the rounded placed therefrom, substantially asset forth.

5. In a scale, in combination, a scale supporting arm, having a pair ofhemispherical projections fixed with relation to the balance bar, abalance bar having trunnions with rounded lower faces adapted to rest inrolling contact upon said hemispherical projections, and a movablecentering cage or device, substantially as set forth.

6. In a scale, in combination, a scale supporting arm, having a pair ofconvex projections, a balance bar, having trunnions with rounded faceswhich rest in rolling contact upon the convex projections of thesupporting arm, a pair of members or plates adapted to be moved to andfrom a position in which they confine between themselves in verticalalinement the trunnions of the balance bar and the convex projections ofthe supporting arm, substantially as set forth.

7. In a scale, in combination, a scale arm, a cage consisting of a pairof plates respectively disposed one on either side of said arm andadapted to be moved in concert to and from a position in which theysnugly embrace but extend above the upper surface of said arm, twohemispherical projections on the upper edge of said supporting arm, anda balance bar provided with cylindrical trunnions which respectivelyrest upon the hemispherical projections of the arm.

8. In a scale or similar device, in combina tion, a supporting armprovided with hemispherical projections, a balance bar havingcylindrical trunnions which rest upon said hemispherical projections, astandard upon which said supporting arm is mounted, a pair of platesforming a cage which plates are dis posed on either side of saidsupporting arm, and means for causing the Vertical movement of said cageas a whole, substantially as set forth.

9. In a scale or similar device, in combination, a supporting armprovided with hemispherical projections, a balance bar havingcylindrical trunnions which rest upon said hemispherical projections, astandard upon which said supporting arm is mounted, a pair of platesforming a cage which plates are dis posed on either side of saidsupporting arm, a follower connected to the cage and mounted on the bodyof the scale standard and movable with relation thereto,and meanssituated at the foot of said scale standard for causing the elevationand depression of said follower, substantially as set forth.

10. In combination, the supporting arm, the balance bar, the cage, thefollower to which said cage is connected, the supporting standard, a keyformed as a cylindrical tube mounted in the foot of said standard, saidtube being partly cut away in the'region beneath said follower,substantially as set forth.

11. In combination, the supporting arm, the balance bar, the cage, thefollower to which said cage is connected, the supporting In testimonythat I claim the foregoing as standard, a key formed as a cylindricaltube my invention I have hereunto signed my IO mounted in the foot ofsaid standard, said name this 2d day of June, A. D. 1899.

tube being partly cut away in the region ber neath said follower, and apin mounted in the TILLIAM MORSELL' interior of said key, said pinbeing, in the In presence of region beneath the follower, ofsubstantially F. NORMAN DIXON,

oblong section, substantially as set forth. THOs. K. LANCASTER.

